JP2002192523A - Method and apparatus for treating glass cloth for resin impregnation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply separate glass filaments in the joined parts of glass cloth mutually by applying stress to the glass cloth not only to enhance the impregnation properties of the glass cloth with a resin but also to suppress the loosening of the texture of the glass cloth. SOLUTION: The glass cloth (5) is passed through the nip between at least a pair of pressure rolls (4) having smooth surfaces to be pressed by the pressure rolls (4).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a treatment of a glass cloth used for a composite material such as a laminate obtained by molding after impregnating a resin, for example, a printed wiring board, and more particularly, to a glass cloth treatment. The present invention relates to a method and apparatus for treating a glass cloth for resin impregnation, which can apply stress to easily separate a joint portion between glass filaments to improve resin impregnating property and suppress roughness of a glass cloth weave. .

[0002]

BACKGROUND OF THE INVENTION A composite material utilizing a glass cloth, in particular, a laminate obtained by impregnating with a resin and then molding is manufactured as follows. First, in order to improve the performance of the laminated board, a glass cloth is subjected to a surface treatment using an organic silane compound (silane coupling agent) to prepare a so-called treated glass cloth. The cloth is impregnated and heat-treated to produce a semi-cured prepreg. Thereafter, the prepreg is cut into a predetermined shape, and a plurality of the prepregs are stacked and subjected to hot pressing to form a desired laminated plate. In addition, in addition, in the case of a copper-clad laminate used for a printed wiring board, for example, a glass / epoxy copper-clad laminate or a glass / polyimide copper-clad laminate, a copper foil is applied on one or both sides during hot pressing. And hot pressing is performed.

[0003] The above-mentioned composite material containing glass cloth is required to have improved mechanical properties such as bending strength and impact resistance. Particularly, in the case of a laminate used for a printed wiring board, heat resistance is required. Improvements in performance such as performance and dimensional stability are also strongly desired. These properties such as mechanical properties, thermal properties, and dimensional stability are greatly influenced by the chemical affinity between the glass cloth and the resin and the physical impregnation. That is, when the affinity between the resin and the glass surface is insufficient,
If the resin is not sufficiently impregnated between the yarns and filaments of the glass constituting the glass cloth, the mechanical properties may deteriorate or the interface between the glass and the resin layer may be separated at high temperatures.
(Blister) and peeling (measling) of the resin layer at the confounding point between the warp and the weft of the yarn.

The glass yarn constituting the above-mentioned glass cloth is usually formed by bundling several hundred monofilaments having a diameter of 5 to 9 μm, twisted lightly in order to maintain the form of the yarn, and a binder and a paste. And a sizing agent or an oil agent. The glass cloth is woven by using the glass yarn as the warp and the weft, and the glass cloth at the so-called greige stage woven in this way has the above-mentioned sizing agent and the like adhered to the glass filament. The sizing agent and the like are removed, and thereafter, a surface treatment is performed with the silane coupling agent described above.

In the glass cloth surface-treated as described above, the sizing agent, its thermal denatured product, excess silane coupling agent, and the like are likely to remain between glass filaments. Formed joints (so-called gaming spots). When this joint is formed, it is difficult to impregnate the resin between the glass filaments. Therefore, the molded glass cloth-containing composite material has mechanical properties, thermal properties, dimensional stability, etc. as described above. Causes a problem that the temperature decreases. Therefore, the glass cloth needs to be subjected to a so-called fiber opening treatment in which the glass filaments of the bonding portion are separated from each other before being impregnated with the resin.

[0006]

2. Description of the Related Art Conventionally, as a method of separating a joint portion between glass filaments, for example, Japanese Patent Laid-Open No.
As disclosed in Japanese Patent No. 7959, there is known a method in which a high-pressure water jet is sprayed on a glass cloth to open a glass filament having high convergence. This conventional method starts with a small diameter of about 0.1 to 0.2 mm and starts at 4.9 to 14.
A high-pressure columnar water stream jetted at a pressure of 7 MPa (50 to 150 kgf / cm2) is sprayed onto the glass cloth, thereby separating the joints between the glass filaments and opening the fiber.
This is to allow the resin to be well impregnated.

[0007]

In the above prior art, since a high-pressure columnar water stream is blown onto the glass cloth, there is a problem that the texture of the glass cloth is roughened, and the generation of fluff due to breakage of the glass filament increases. There are also problems. The roughness of the weave may cause a decrease in mechanical properties of the glass cloth or a composite material using the same, and the generation of fluff is likely to cause irregularities on the surface of the prepreg, and the printed wiring board In such a case, there is a fear that the copper foil to be overlaid on the prepreg is damaged and circuit failure occurs. In addition, the above-mentioned prior art requires a high ejection pressure,
Drying for removing water after the treatment is necessary, and there is a problem that energy cost and equipment cost are high.

The present invention solves the above-mentioned problems, and applies a pressing force to the glass cloth to easily separate the glass filaments at the joining portion to improve the impregnation property of the resin, and to further improve the texture of the glass cloth. It is a technical object of the present invention to provide a method for treating a glass cloth for resin impregnation and an apparatus for treating the glass cloth for resin impregnation.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, the impregnating property of the resin has been greatly increased by pressing the glass cloth with a pair of pressure rolls. And reached the present invention. That is, the invention according to claim 1 relates to a method for treating a glass cloth for resin impregnation, wherein the glass cloth (5) is passed between at least a pair of pressure rolls (4) having a smooth surface,
By pressing the glass cloth (5) with the pressing roll (4), the joining portion between the glass filaments constituting the glass cloth (5) is separated to improve the impregnation property of the resin. .

The invention according to claim 4 relates to an apparatus for treating a glass cloth for resin impregnation, comprising at least one pair of pressure rolls (4) having a smooth surface.
(4) The glass cloth (5) is passed through and pressed between the glass cloths (5) and pressed to separate the joints between the glass filaments constituting the glass cloth (5).

[0011]

The glass yarn constituting the glass cloth is flattened by a relatively light pressing force of the pressing roll, and the bonding state of the glass filaments is broken, so that the glass yarn is easily separated. At this time, only a uniform pressing force is temporarily applied to the entire glass cloth, and there is no change in the cloth structure such as coarse texture, and the generation of fluff due to the breakage of the filament can be suppressed to a low level.

The pressing force of the pressing roll is usually
The linear pressure is set to 10 to 1000 N / cm, more preferably 50 to 500 N / cm. In addition, although only one pair of pressure rolls may be provided to allow the glass cloth to pass only once, a plurality of pressure rolls may be provided and pressed multiple times by passing between these pressure rolls. Thus, the glass filaments can be satisfactorily separated from each other, and in this case, the impregnating property of the resin can be further improved.

The glass cloth may be passed between the pressing rolls in a dry state. In this case, unlike the prior art, a drying step is not required at the subsequent stage, which is preferable. However, if the glass cloth is wetted beforehand and passed between the pressing rolls in this wet state, moisture exists between the glass filaments, so that the glass filaments do not disturb the texture. This is more preferable because it is easy to move in the range, easily opened, and the glass yarn is further flattened, and the distribution of the glass filaments becomes more uniform.

In this case, the glass cloth is wetted by immersing the glass cloth in a water tank disposed at a stage prior to the processing step with respect to the pressing roll, or spraying water on the glass cloth. It is also conceivable to arrange the press roll in water. In addition,
A surfactant or the like may be added to the water added to the glass cloth to improve the penetration of the water between the glass filaments.

The glass filament constituting the above-mentioned glass cloth may be of any glass component. For example, E glass, C glass, S glass and the like are preferable, and particularly, glass suitable for a glass cloth used for a printed wiring board. Is preferably non-alkali glass E glass.
As the fiber diameter of the glass filament, any fiber diameter can be used as long as a glass cloth can be woven, but a fiber diameter of several μm to several tens μm is preferable.

The glass cloth used in the present invention is obtained by subjecting a glass yarn obtained by combining a plurality of such glass filaments to a warping step and a sizing step, and then weaving the glass yarn. May be any other than plain weave, twill weave, satin weave, triaxial weave and the like. The number of warps and wefts per unit length, thickness, and weight per unit area of the glass cloth are preferably those corresponding to R-3414 of the Japanese Industrial Standards or the United States Military Standards (MIL standard), The invention is not limited to this, and any one can be used. The thickness of the glass cloth corresponding to the above standard is about 20 to 300.
μm, and the weight is about 20 to 350 g / m ² .

The glass cloth used in the present invention includes not only glass cloth in a range not conforming to these standards, but also a woven fabric composed of glass filaments and other fibers, such as carbon fiber, organic fiber, and ceramic fiber. A cloth or the like made of a mixed weave may be used.

The glass cloth to which the present invention is applied is a glass cloth in a greige stage to which a sizing agent necessary for weaving is adhered, a cleaned glass cloth in a stage in which the sizing agent is removed by a wet treatment or a dry treatment, and a greige machine. Alternatively, it may be a glass cloth at any stage, such as a glass cloth having a cleaned cloth surface-treated with an organic silane compound.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic perspective view of a processing apparatus for a glass cloth for resin impregnation, showing a first embodiment of the present invention.

As shown in FIG. 1, this processing device (1)
A metal pressing roll (2) and a hard rubber or FRP supporting roll arranged opposite to the pressing roll (2)
And (3) a pair of pressurizing rolls (4) comprising
The glass cloth for resin impregnation (5) is guided between the pressing roll (2) and the support roll (3).

The glass cloth (5) guided between the above-mentioned pressing rolls (4) is sandwiched between the pressing roll (2) and the supporting roll (3) and has a linear pressure of 10 to 1000 N / cm, preferably. It is pressed at 50 to 500 N / cm. By this pressing, the tension of the glass yarns constituting the glass cloth (5) is well balanced, the distribution of the glass filaments in the glass cloth (5) becomes more uniform, and the bonding state of the glass filaments at the gamming spot is improved. When broken, the glass filaments separate from each other. Thereby, the impregnating property of the resin into the glass cloth is improved.

At this time, the pressing force of the pressing roll (4) is temporarily and uniformly applied only when the glass cloth (5) passes between the pressing rolls (4). The texture of the cloth (5) is maintained in a normal state,
Moreover, the generation of fluff due to the breakage of the glass filament can be suppressed to a low level.

Next, the present invention will be specifically described with reference to examples and comparative examples using the above-described processing apparatus (1).

[0024]

Example 1 Using the above-mentioned processing apparatus (1) equipped with a pair of pressurizing rolls (4) composed of an iron press roll (2) and an FRP support roll (3), a thickness of 100 μm and a density warp 60
A glass cloth (produced by Unitika Glass Fiber Co., Ltd., product number: E10T 4WT) having a total of 58 × 25 wefts / 25 mm and a yarn usage of 7 μm × 200 was processed. The pressing force of the press roll is 5 to 50 kgf / cm (about 50 to 500 N / cm) in linear pressure.
And then passed between pressurizing rolls one or more times to measure the resin impregnation property of the obtained treated glass cloth, and the pressure treatment using the same glass cloth was not performed This was compared with Comparative Example 1.

The resin impregnating property is determined by cutting a test piece of approximately 5 cm square from an arbitrary portion of a glass cloth and placing the test piece under a stereoscopic microscope on a commonly used epoxy varnish for FR-4. Was added dropwise, and the time until the so-called void, which was not impregnated with the resin, disappeared, was measured, and the average value was determined to evaluate. Table 1 shows the evaluation results.

[0026]

[Table 1]

[0027]

Example 2 Using the same processing apparatus (1) as in Example 1, a thickness of 180 μm, a density of 42 warps × 32 wefts / 25 mm,
A glass cloth (product number E18T 4WT, manufactured by Unitika Glass Fiber Co., Ltd.) of 9 μm × 400 yarns was processed. The pressing force of the pressing roll is 10 to 50 in linear pressure.
kgf / cm (about 100-500N / cm)
One or more times, between the pressure rolls, the resin impregnating property of the obtained treated glass cloth was measured in the same manner as in Example 1 above, and the pressure treatment was performed using the same glass cloth. Comparative Example 2 was not used. Table 2 shows the evaluation results.

[0028]

[Table 2]

[0029]

Example 3 Using the same processing apparatus (1) as in Example 1 above, a thickness of 60 μm, a density of 54 warps × 54 wefts / 25 m
m, a 5 μm × 200 glass cloth (unit number E06C greige manufactured by Unitika Glass Fiber Co., Ltd.) was used. The pressing force of the press roll is 5 to 50 kg in linear pressure.
f / cm (approximately 50 to 500 N / cm), and pass through the press rolls one or more times to measure the degree of flattening of the glass yarn of the obtained treated glass cloth. Then, a comparison was made with Comparative Example 3 in which the same glass cloth was not subjected to the pressure treatment.

The degree of flattening of the glass yarn was measured at several points from an arbitrary portion of the glass cloth using a microplotter (manufactured by Mutoh Kogyo Co., Ltd.). Table 3 shows the evaluation results.

[0031]

[Table 3]

[0032]

EXAMPLE 4 Using the same processing apparatus (1) as in Example 1, a glass cloth (Unitika Glass Fiber Co., Ltd.) having a thickness of 30 μm, a density of 70 warps × 70 wefts / 25 mm, and a yarn use of 4 μm × 130 , Part number E03C greige). The pressing force of the pressing roll is 10 to 40 kg in linear pressure.
f / cm (approximately 100 to 400 N / cm), and passed one or more times between the pressing rolls to determine the degree of flattening of the glass yarn of the obtained treated glass cloth. The measurement was performed in the same manner as in Example 3, and the result was compared with Comparative Example 4 in which the same glass cloth was not subjected to the pressure treatment. Table 4 shows the evaluation results.

[0033]

[Table 4]

[0034]

FIG. 2 shows a second embodiment of the present invention.
It is a schematic structure figure of a processing device of a glass cloth for resin impregnation.

As shown in FIG. 2, in the second embodiment, similarly to the first embodiment, a metal pressing roll (2) is used.
And a hard rubber or FR disposed opposite to this
A pair of pressure rolls composed of a P support roll (3)
(4), and furthermore, a bat (6) as a wetting device is provided at a stage preceding the processing step with respect to the installation position of the pressing roll (4).

First, the glass cloth (5) is
It is immersed in water in the inside to be in a wet state, and then guided between the pressing roll (2) and the supporting roll (3) of the pressing roll (4), and pressed similarly to the first embodiment. It is processed. In this case, moisture has penetrated between the glass filaments constituting the glass cloth (5), and the presence of the moisture makes it easy for the glass filaments to move within a range that does not disturb the texture. As a result, due to the pressing by the pressing roll (4), the joint between the glass filaments is separated, and the glass yarn is more easily flattened, and the distribution of the glass filaments becomes more uniform.

[0037]

Fifth Embodiment In the second embodiment, the processing apparatus (1) provided with a pair of pressurizing rolls (4) including a pressing roll (2) made of iron and a supporting roll (3) made of FRP is used. Use
Thickness 100μm, density warp 60 × weft 58 / 25m
m, thread cloth 7 μm × 200 glass cloth (Unitika Glass Fiber Co., Ltd., product number K10T344 4WT)
Was processed. The pressing force of the press roll is 5 to 5 in linear pressure.
Change in the range of 50 kgf / cm (about 50-500 N / cm),
The resin impregnating property of the treated glass cloth obtained by passing between the pressure rolls once or more than once is determined in Example 1 above.
Was measured in the same manner as in Example 1 and compared with Comparative Example 5 in which the same glass cloth was not subjected to the pressure treatment. Table 5 shows the evaluation results.

[0038]

[Table 5]

[0039]

Embodiment 6 Using the same processing apparatus (1) as in Embodiment 5, a thickness of 180 μm, a density of 42 warps × 32 wefts / 25 mm,
A glass cloth (product number E18T 4WT, manufactured by Unitika Glass Fiber Co., Ltd.) of 9 μm × 400 yarns was processed. The pressing force of the pressing roll is 10 to 50 in linear pressure.
kgf / cm (about 100-500N / cm)
One or more times, the resin was passed through a pressure roll, and the resin impregnating property of the obtained treated glass cloth was measured in the same manner as in Example 1, and the pressure treatment was performed using the same glass cloth. Comparative Example 6 was not used. Table 6 shows the evaluation results.

[0040]

[Table 6]

In each of the above embodiments, the case where a pair of pressurizing rolls is used has been described. Cleaned glass cloth, such as a glass cloth surface-treated with an organic silane compound, it is possible to arrange a pair or a plurality of pairs of pressure rolls for any stage of the glass cloth,
Furthermore, it is also possible to arrange in each of a plurality of processes. In each of the above embodiments, each of the pressing rolls is made of iron.
Pressing roll (4) with (2) and FRP supporting roll (3)
However, the press roll of the present invention may be any roll that can press the glass cloth, and any roll is not limited to a specific material.

[0042]

Since the present invention is constructed and operates as described above, it has the following effects.

(1) Since the glass yarn constituting the glass cloth is temporarily and uniformly pressed by the pressing roll, the glass yarn is flattened with a relatively light pressing force, and the joint between the glass filaments is easily formed. Can be separated,
A glass cloth having a high resin impregnation property can be easily obtained.

(2) In addition, since a strong local pressing force or water pressure is not applied to the entire glass cloth, the cloth structure is not changed, for example, the texture is roughened, and the generation of fluff due to the breakage of the filament is prevented. It can be kept low.

(3) Unlike the prior art, since a high-pressure water flow is not used, equipment that can withstand high pressure is not required, and the equipment cost and energy cost can be reduced and the cost can be reduced.

(4) When the glass cloth is wetted in advance and the wet glass cloth is passed between the pressing rolls, the glass filaments are textured by the moisture permeated between the glass cloths. Therefore, the glass yarn can be spread easily and the glass yarn can be more easily flattened, and the distribution of the glass filaments can be made more uniform.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of an apparatus for processing a glass cloth for resin impregnation, showing a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a processing device for a glass cloth for resin impregnation, showing a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Processing apparatus, 2 ... Press roll, 3 ... Support roll,
4: Roll for pressing, 5: Glass cloth for resin impregnation,
6 ... wetting device (bat).

Continued on the front page F term (reference) 3B154 AA13 AB20 BA14 BB02 BC22 BF02 DA21 DA30 4F072 AB09 AB28 AB29 AC01 AC03 AD23 AG16 4F205 AD16 AH36 HA14 HA33 HB01 HC05 HC16 HE16

Claims (5)

[Claims] 1. A glass cloth (5) is passed between at least a pair of pressing rolls (4) having a smooth surface, and the glass cloth (5) is pressed by the pressing roll (4). A method for treating a glass cloth for resin impregnation, comprising separating a joint portion between glass filaments constituting a glass cloth (5) to improve resin impregnation. 2. The resin impregnation according to claim 1, wherein the glass cloth (5) is wetted beforehand, and the wet glass cloth (5) is passed between the pressure rolls (4). Processing method of glass cloth. 3. A linear pressure of 10 by the pressing roll (4).
The glass cloth is pressed at a pressure of up to 1000 N / cm.
Alternatively, the method for treating a glass cloth for resin impregnation according to claim 2. 4. A glass cloth, comprising at least a pair of pressure rolls (4) having a smooth surface, wherein a glass cloth (5) is passed between the pressure rolls (4) and pressed.
(5) An apparatus for treating a glass cloth for resin impregnation, wherein a joint between glass filaments constituting (5) is separable. 5. A wetting device (6) is provided on the upstream side of the processing step from the installation position of the pressing roll (4), and the glass cloth (5) previously wetted by the wetting device (6) is used for the pressing. The apparatus for treating a glass cloth for resin impregnation according to claim 4, wherein the apparatus is configured to be guided between the rolls (4).